Throughout this application, various publications are referenced. Disclosures of these publications in their entireties are hereby incorporated by reference into this application to more fully describe the state of the art to which this invention pertains.
At the present time, there are a few single-serving type coffee (and beverage) machines out in the market, which can make a good cup of high quality coffee easily, conveniently and instantly. However, it could be quite cumbersome and inconvenient for the user if he or she needs to make many cups of coffee or beverage for a large group of people at the same time using a single-serving type coffee or beverage machine, as the user would need to repeat the same operation many times. Although the overall actual brewing time of a typical single-serving machine is still faster than conventional drip-type coffee machines, it is still too much work and too tedious for the user to make one cup of coffee at a time for a group of people.
At the present time, there are also a few combined coffee machines in the market, which are capable of brewing coffee and espresso simultaneously or independently. However, these machines are more costly and are more prone to breakdown or malfunction because they contain additional parts, such as two heating systems.
Generally, combined coffee machines in the market use a horseshoe type heater for making regular drip coffee, and a boiler system for making espresso coffee. Most combined machines combine two separate systems into one unit rather than sharing a single system with shared or common components, including but not limited to heaters, boilers and control system, for making different types and amounts coffee or beverage as the machine of the present invention.
European Patent No. 1086641 discloses a combined coffee machine and steam generator having a multi-switching valve which in one position connects water reservoir to water heater and allows hot water to be fed to riser pipe leading to coffee filter container and in second position allows limited quantity of water to be fed to pressure store via separately filling funnel for heating via water heater. A related Italian Patent (IT 1249124) discloses a machine comprising a pump connected to a boiler. The said machine has a control system which controls the flow of water into the boiler. By actuating a switch, the user sets the machine to one mode to make strong coffee. By switching the machine to coffee-filter mode the control system is activated to control the pump and heating elements or boiler.
The above-mentioned coffee machines have many drawbacks and limitations, which are summarized below:    1. Only one module of coffee machines mentioned above can be used at a time. However, the system or machine of the present invention can use either one or both modules to make a cup and/or a jug of coffee at the same time.    2. The single-serving module of the coffee machine mentioned above produces very strong espresso coffee using the method of conveying highly pressurized, i.e. 6–12 bar, and superheated water through the fine ground coffee to make espresso coffee. However, the system or machine of the present invention produces regular coffee by the method of pumping the low pressure (below 3 bar) water through coffee pod or ground coffee.    3. The boiler system of the coffee machine mentioned above is used for making both espresso coffee and steam, which required higher water temperature, i.e. over 100° C. Hence the hot water temperature for brewing filter coffee is superheated. The system or machine of the present invention uses an electronic temperature control device to control and maintain the hot water at the desired temperature, i.e. below 100° C., which is always suitable for making a cup or a jug of regular coffee.    4. The coffee machines mentioned above uses high pressure type boiler, i.e. closed type boiler, which can also produce steam. The system or machine of the present invention uses a low pressure displacement type boiler, which is open to the atmosphere, and is easier to maintain or repair, cost less to manufacture, and has a longer operating life. The boiler of the present invention cost less than high pressure boilers because thinner materials can be used to manufacture boilers which are suitable for low pressure applications.
An object of the present invention is to provide a multipurpose coffee- or beverage-making machine having a flow controller which in one position connects the water reservoir or external water supply, pump and water heater which are connected in series by suitable piping to a single-serving coffee brewing chamber or module, and in a second position to a multi-serving coffee brewing chamber or module.
In another aspect of the present invention, the single-serving and multi-serving brewing chamber or module can operate alone independently or simultaneously without affecting the quality of the brewed coffee or beverage.
In another aspect of the present invention, the outlet temperature of the heated water from the boiler, the flow rate, pressure, and the amount of flow of the heated water to each brewing chamber or module are controlled and monitored by a control system.
In another aspect of the present invention, the single-serving brewing chamber or module is adapted to brew prepackage coffee pods (or pads).
The benefits of the present invention are outlined below:    1. By sharing common components, including but not limited to the pump, water reservoir and boiler, the coffee or beverage machine would be more cost effective, smaller in size, and more reliable as there is less chance for the machine to malfunction or breakdown.    2. Through the use of an electric pump, the user can program the coffee or beverage machine to brew the desired number of cups of coffee or beverage, thus minimizing waste. Most conventional household drip-type coffee makers use heating element only, thus they can not control the amount of water to dispense.    3. The multi-serving brewing chamber or module of this invention can also brew high quality coffee, similar to the single-serving brewing chamber or module, by using a control system to control, maintain and optimize the water temperature, water flow rate, and optimal coffee brewing time or the amount of time the heated water is in contact time with the coffee grounds.    4. Since the machine of the present invention uses an electric pump, the location or position of the water tank/reservoir is more flexible because the appropriate water head (water pressure) needed to deliver the water from the water tank or reservoir to the brewing chamber or module will be a concern. The water supply or reservoir can be placed in front or on the side of the machine. The water can even be plumbed into the machine directly from the water pipes.
The foregoing objects and advantages of the present invention are illustrative of those that can be achieved by the present invention and are not intended to be exhaustive or limiting of the possible advantages which can be realized. Thus, these and other objects and advantages of the invention will be apparent from the description herein or can be learned from practicing the invention, both as embodied herein or as modified in view of any variation which may be apparent to those skilled in the art. Accordingly, the present invention resides in the novel methods, arrangements, combinations and improvements herein shown and described.